By

Richard Peet, J.D., Ph.D.

GUT MICROBES: WHAT IF THEY GO EXTINCT?

Scientists Fear Microorganisms in the Human Microbiota May Go the Way of the Dinosaurs
Should We Care?

THE SHORT ANSWER: YES! The human gut is host to trillions of living organisms that help to process food during digestion and contribute to health and wellbeing. If good microbes become extinct, bad microbes will colonize our colon and wreak havoc. Without the right microbes in our gut microbiota, research indicates that we increase the likelihood of suffering from obesity, diabetes, inflammation, cardiovascular disease, and other chronic illnesses. As in all ecosystems, every creature plays a part in maintaining a healthy balance; extinction of microbes can destroy the delicate ecology of our internal gut physiology.

WHY IT MATTERS: It is often said that a dog is man’s best friend. Did you know that the same should be said about the bacteria, archaea, fungi, and viruses that live in your large intestine? Collectively, these microorganisms are called the microbiota. Scientists estimate that
the number of microorganisms that comprise the microbiota exceeds all the cells in the human body! Unbeknownst to you, some microbes live in harmony with your body, eating, sheltering, and thriving without hurting you (called commensal by biologists, from the Latin, “to eat at the same table”). Others live with you in a symbiotic relationship (one that is mutually beneficial to both organisms), while others are pathogenic (i.e., disease causing).

IT TAKES A VILLAGE: It is hard to imagine that armies of microbes are battling for dominance inside your gut. Most people, including your physician, may not know that humans depend on gut microbes for health and wellbeing. A delicate balance exists among portions of the microbiota that help human’s digest food for energy and strength. Other microbes serve no valuable purpose; some interact with the human host in ways that cause illness. Therefore, it is essential to understand that you and your microbiota are in a co-dependent
relationship. After millions of years of co-evolution between humans and the wide diversity of microorganisms within our bodies, these microbes are dependent on humans for food and shelter, and humans have become dependent on our microbiota for health and wellbeing. It’s symbiotic!

ENDANGERED SPECIES? All organisms need food and the right habitat to survive. This goes for the microbiota as well. By analogy, cutting down the Amazon rainforest leads to the extinction of animals and plants that lose their habitat and food. Unfortunately, because our gut is
out of sight and out of mind, we may not be feeding good microbes the food they need to survive. As they die and potentially become extinct, our gut dramatically changes and does not support our health and wellbeing.

FEED YOUR MICROBOTA THE FOODS THEY NEED: Prebiotics are the foods that good microbes need, substances found in fruits, vegetables, and grains. Surprisingly, humans have no capacity to digest prebiotics substances. These raw materials pass through our digestive tract
until they arrive in the large intestine, where the microbiota break down prebiotic substances into metabolites that are food for gut microorganisms and nutrients for the human host such as vitamins and substances that ward off pathogens. Over millions of years of co-evolution, microbes in our digestive tract have become dependent on humans consuming fruits, vegetables, and grains for their survival; humans, therefore, must feed the microbes the right food or they will die. In a mutually beneficial way, the microbiota processes portions of what we eat and contribute to sustaining our daily lives.

HELP! Unfortunately, the American diet is contributing to the extinction of the microbiota necessary for our health. On average, Americans consume 60% of their calories each day from ultra-processed foods containing little of the whole food ingredients from fruits, vegetable, and grains. Ultra-processed foods are formulations made from substances derived from foods, with little if any intact food. Ultra-processed food typically contain a mix of several ingredients such as sugars, fats, oils, proteins, modified starches, and additives. Ultra-processed foods are designed to be convenient (long shelf-life or ready-to-eat), palatable and addictive, and highly profitable. Consumption of large amounts of these ultra-processed foods results in gut microbes that may be malnourished, deprived of the foods they need to live and flourish, and could slowly become extinct.

THE BIG PICTURE: Much attention is being paid to climate change and how greenhouse gases are damaging the earth’s atmosphere, and creating an existential threat to human survival. A similar existential crisis is happening inside our bodies. We know the symptoms: problems with weight management, diabetes, inflammation, heart disease, immune deficiencies, cancer, and brain health. We are not addressing the root cause of such maladies. We are relying on pills (sick care) instead of proper nutrition (health care). We are not making certain fresh fruits, vegetables, and grains readily available and affordable to everyone in our society resulting in an epidemic of chronic disease.

THE DETAILS: In future blogs, I will:

  1. Help you to understand what is happening inside your gut and the importance of the
    microbiota.
  2. Evaluate data showing certain gut bacteria may motivate us to exercise.
  3. Identify substances in human milk that an infant can’t digest but microbes in the infant
    gut can rely on for food.
  4. Explain short chain fatty acids and why you should care what they are.
  5. Evaluate what we know about gut microbes, illness, and disease.
  6. Discuss how to feed your gut microbes the prebiotics they need.
  7. Describe the whole human and the role of the microbiota.
  8. Consider fruits, vegetables and grains and what prebiotic substances they contain.

I would like to thank my friend Michael B. Reiner, Ph,.D. for editing some of these blogs.  Any errors in the blogs are solely my responsibility.